Abstract

As regards the issue of futura contingentia, Aquinas's interpretation turns on a phrase that has sometimes been dismissed as irrelevant or even confused: "...non tamen haec vel illa determinatae...". It is shown that this clause is in complete conformity with Aquinas's interpretation of the principles of non-contradiction and of excluded middle. According to this interpretation the meaning of propositional negation derives from the first two principles considered collectively but is not presupposed by them. With respect to time-relative modalities this implies that at the time of announcement, say, of a sea battle both parts of the contradiction could be true, provided one understands "could" in the sense of a counterfactual possibility with respect to the final outcome. It is also shown that Aquinas's interpretation allows one to avoid some perplexities in connection with the controversial beginning of Met. IX, 4. Some final considerations are meant to show the rationale of that interpretation